Suture passer and method

ABSTRACT

Instruments and techniques to pass a suture, particularly in instances where access to confined spaces and the ability to pass a suture through difficult to penetrate materials are needed. The instruments and techniques are particularly useful in surgery of the hands and feet.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/568,137, filed Dec. 7, 2011, U.S. Provisional Application No.61/505,992, filed Jul. 8, 2011, U.S. Provisional Application No.61/506,000, filed Jul. 8, 2011, U.S. Provisional Application No.61/506,004, filed Jul. 8, 2011, all of which are herein incorporated byreference.

FIELD OF THE INVENTION

The invention relates to devices and methods to pass a suture and, inparticular, to suturing material such as, for example, soft tissue inreconstructive surgery of a joint such as for example of the foot orhand.

BACKGROUND

Various conditions affecting a patient may require surgical interventioninvolving passing a suture for example to repair a tear, repair anincision, pass grafts, attach grafts, and anchor implants. Varioussuture passers have been proposed. There is a need for an improvedsuture passer able to access confined spaces and able to pass a suturethrough difficult to penetrate materials such as tough connectivetissues.

SUMMARY

The present invention provides a suture passer and method to pass asuture through material during a surgical intervention.

In one aspect of the invention a suture passer includes a housingdefining a linear motion axis extending proximally to distally and aneedle mounted for translation along the motion axis between a firstproximal position and a second distal position. The suture passer mayinclude a foot mounted to the housing and having an opening in aproximal facing surface to receive the needle in the second position.

In another aspect of the invention a suture passer includes a housing, aneedle, and a foot and the foot includes a passage from a distal facingsurface to an exit adjacent a needle receiving opening. A groove may beformed in a proximally facing surface adjacent the passage and a notchmay be formed in the distal end of the foot adjacent the groove suchthat the passage, groove and notch are able to receive a suture throughthe distal portion, across the needle receiving opening, along theproximally facing surface, and around the distal end.

In another aspect of the invention, a suture passer includes a housing,a needle mounted for motion between a first position and a secondposition, and a foot. The foot may position a suture in the path of theneedle. The needle may have a notch engageable with the suture in thesecond position and impart a proximally directed force on the suture asthe needle moves toward the first position. The needle may have a shaftwith a bevel engageable with the suture to deflect the suture away fromthe needle axis as the needle is moved toward the second position. Thenotch may have a width and a depth. The width and depth may be relatedto the diameter of the suture. The width and depth may be related to thecompliance of the suture.

In another aspect of the invention, a method of passing a suture througha material includes positioning a distal portion of a foot of a suturepasser behind the material, extending a needle through the material; andretracting the needle to retrieve a bight of suture from the distalportion proximally through the material. The method may includeretrieving multiple, connected bights of suture through the material toform a running stitch.

BRIEF DESCRIPTION OF THE DRAWINGS

Various examples of the present invention will be discussed withreference to the appended drawings. These drawings depict onlyillustrative examples of the invention and are not to be consideredlimiting of its scope.

FIG. 1 is a perspective view of an illustrative example of a suturepasser according to the present invention;

FIG. 2 is an exploded perspective view of the suture passer of FIG. 1;

FIG. 3 is a front elevation view of a component of the suture passer ofFIG. 1;

FIG. 4 is a is a side elevation view of the component of FIG. 3;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4;

FIG. 6 is a side elevation view of the suture passer of FIG. 1;

FIG. 7 is a top plan view of the suture passer of FIG. 1;

FIG. 8 is a sectional view taken along line 8-8 of FIG. 7;

FIG. 9 is a perspective view of a component of the suture passer of FIG.1;

FIG. 10 is a side elevation view of the component of FIG. 9;

FIG. 11 is a bottom plan view of a component of the suture passer ofFIG. 1;

FIG. 12 is a side elevation view of the component of FIG. 11;

FIG. 13 is a sectional view taken along line 13-13 of FIG. 12;

FIGS. 14A-G are bottom plan views of variations of the component of FIG.11;

FIG. 15 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating a suture being loaded on thesuture passer;

FIG. 16 is a top plan view of the distal end of the suture passer ofFIG. 1 illustrating a suture being loaded on the suture passer;

FIG. 17 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating a suture being loaded on thesuture passer;

FIG. 18 is a top plan view of the distal end of the suture passer ofFIG. 1 illustrating a suture being loaded on the suture passer;

FIG. 19 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating a suture being loaded on thesuture passer;

FIG. 20 is a top plan view of the distal end of the suture passer ofFIG. 1 illustrating a suture being loaded on the suture passer;

FIG. 21 is a perspective view of the suture passer of FIG. 1illustrating a suture being loaded on the suture passer;

FIG. 22 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating the operation of the suturepasser;

FIG. 23 is a top plan view of the distal end of the suture passer ofFIG. 1 illustrating the operation of the suture passer;

FIG. 24 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating the operation of the suturepasser;

FIG. 25 is a top plan view of the distal end of the suture passer ofFIG. 1 illustrating the operation of the suture passer;

FIG. 26 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating the operation of the suturepasser;

FIG. 27 is a partially sectioned side elevation view of the distal endof the suture passer of FIG. 1 illustrating the operation of the suturepasser; and

FIGS. 28-46 are perspective views illustrating the suture passer of FIG.1 in use to pass sutures through a material to create a variety ofstitches.

DESCRIPTION OF THE ILLUSTRATIVE EXAMPLES

The following illustrative examples depict instruments and techniques topass a suture through a material. Instruments and techniques accordingto the present invention may be used to pass a suture through anymaterial, at surgical sites anywhere in a patient's body, and for anypurpose. Instruments and techniques according to the present inventionare particularly useful where access to confined spaces and the abilityto pass a suture through difficult to penetrate materials are needed.For example, surgery on the hands and feet often involve working inconfined spaces around small joints and tough connective tissues throughwhich it may be desirable to pass a suture. The terms “suture” and“suture strand” are used herein to mean any strand or flexible member,natural or synthetic, able to be passed through material and useful in asurgical procedure. The term “material” is used herein to mean implants,grafts, fabric, tendon, ligament, fascia, skin, muscle, bone, and anyother material through which it is desirable to pass a suture. The term“transverse” is used herein to mean crossing as in non-parallel. Theterm “bight” is used herein to mean a bend or loop formed in theintermediate portion of a suture.

FIGS. 1-13 depict an illustrative example of a suture passer 100. Thesuture passer 100 includes a housing 200, a needle assembly 300, and abarrel assembly 400 mounted together and operable to translate theneedle assembly 400 between a first, retracted position and a second,extended position to manipulate a suture strand.

The housing 200 includes a hollow receiver portion 202 having a hollowthrough bore 204 with a longitudinal bore axis 206. An enlarged counterbore 208 is formed coaxial with the through bore 204 at a distal end 210of the receiver 202. An intermediate portion 212 of the through bore 204has flat side walls 214. A handle 220 extends downwardly and proximallyfrom the receiver 202 and has a longitudinal handle axis 222. The handleaxis 222 forms an angle 224 with the bore axis 206. The angle 224 is inthe range of 90 to 180 degrees; preferably 100 to 140 degrees; morepreferably 110 to 130 degrees. In the illustrative example of FIGS. 1-3,the angle 224 is 120 degrees. A gusset 226 extends between the handle220 and the receiver 202 for strength. One or more knobs extend from thehousing to provide suture strand anchor or routing points. In theillustrative example of FIGS. 1-3, first and second opposed side knobs228, 230 and a downwardly projecting bottom knob 232 are mounted to thereceiver 202. Each knob has a narrow waist 234 and an enlarged head 236as shown with reference to the bottom knob 232. A suture strand may bewrapped or tied around the waist 234 to secure or route the suture.O-rings 238, 240 are provided on the side knobs 228, 230 to grip awrapped suture to facilitate securing and removing a suture strand. As asuture is wrapped around the side knobs 228, 230, it wedges between theresilient O-ring 238, 240 and knob compressing the O-ring. The pressureof the O-ring pressing the suture strand against the knob as well as thedeformation of the O-ring around the suture strand temporarily securesthe suture.

The needle assembly 300 includes a piston 310, a stem 330, a needle 350,and a button 390. The piston 310 has a generally cylindrical body 312with a longitudinal axis 316 extending from a proximal end 318 to adistal end 320. A flange 322 extends radially outwardly from the body312 near the distal end 320. The flange has opposed flattened sides 324.A bore 326 (FIG. 8) is formed coaxially in the piston 310 at the distalend of the body 312. The stem 330 includes an elongated hollow cylinder332 having an outer diameter and an inner bore 334 defining alongitudinal axis 336 extending from a proximal end 338 to a distal end340. The needle 350 is a generally cylindrical member having a shank 352with an outer diameter defining a longitudinal axis 354 extending from aproximal end 356 to a distal tip 358. A flange 360 extends radiallyoutwardly from the shank 352 at a position intermediate the proximal anddistal ends. The needle 350 will be described in greater detail below.The button 390 has a generally cylindrical body with a longitudinal axis391 extending from a proximal end 393 to a distal end 395. A bore 398(FIG. 8) is formed coaxially in the button 390 at the distal end 395 ofthe body. The proximal portion of the needle shank 352 fits within theinner bore 334 of the stem at its distal end 340. The stem outerdiameter, near its proximal end 338, fits within the bore 326 of thepiston 310. The outer diameter of the piston 310 fits within the bore204 of the receiver 202 in linear sliding relationship. The flat sides324 of the piston engage the flat side walls 214 of the bore 204 toprevent the needle assembly from rotating relative to the receiver 202.The piston flange 322 abuts the proximal end of the intermediate portion212 of the bore 204 of the receiver 202 to provide a stop to needleassembly proximal translation relative to the receiver 202. The outerdiameter of the piston 310, near its proximal end, fits within the bore398 of the button 390 and the button 390 abuts a proximal end 216 of thereceiver to provide a stop to needle assembly distal translationrelative to the receiver 202. The joints between the button 390 andpiston 310, the piston 310 and the stem 330, and stem 330 and needle 350are secured by pressing, gluing, pinning, welding, or other suitablesecuring means. Alternatively, two or more of these components orvarious combinations of them may be made as a single piece.

The barrel assembly 400 includes a barrel bushing 410, a barrel 430, anda foot 450. The bushing 410 has a generally cylindrical body 412 havinga through bore 414 with a longitudinal axis 416 extending from aproximal end 418 to a distal end 420. A flange 422 extends radiallyoutwardly from the body 412 at a position intermediate the proximal anddistal ends. An enlarged counter bore 424 (FIG. 8) is formed coaxialwith the through bore 414 at the distal end 420 of the body 412. Thebarrel 430 includes an elongated hollow cylinder 432 having an outerdiameter and an inner bore 434 defining a longitudinal axis 436extending from a proximal end 438 to a distal end 440. The foot 450 is agenerally hook-shaped member having a hollow post 452 having an outerdiameter and an inner bore 454 defining a longitudinal axis 456extending from a proximal end 458 of the cylinder to a distal end 460 ofthe foot 450. The foot will be described in greater detail below. Thefoot post 452 outer diameter fits within the inner bore 434 of thebarrel at its distal end 440. The barrel 430 outer diameter, near itsproximal end 438, fits within the counter bore 424 of the bushing. Acoiled compression spring 250 fits coaxially over the needle assembly300 within the bore 204 of the receiver 202 and rests against the distalend of the piston flange 322. The barrel assembly 400 fits coaxiallyover the needle assembly 300 and the outer diameter of the bushing 410,near its proximal end 418, fits within the counter bore 208 of thereceiver 202 and is pressed proximally until the flange 422 abuts thereceiver distal end 210. The proximal end of the bushing retains thespring 250 within the bore 204. The joints between the foot 450 andbarrel 430, the barrel 430 and bushing 410, and the bushing 410 andreceiver 202 are secured by pressing, gluing, pinning, welding, or othersuitable securing means. Alternatively, the bushing, barrel, foot, orany combination of them may be made as a single piece. Pressing thebutton 390 distally translates the needle assembly from a first,proximal, retracted position distally along the needle axis 354compressing the spring 250 and extending the needle 350 through the foot450 to a second, distal, extended position. Releasing the button 390allows the spring 250 to expand and bias the needle assembly 300 backtoward the first position. The needle assembly 300 of the illustrativeexample of FIGS. 1-13 is a linear arrangement mounted for linear,coaxial translation in the housing 200 and barrel assembly 400 with theneedle projecting straight through the foot to increase rigidity andpower facilitating driving the needle 350 through difficult to penetratematerials and access confined spaces. The barrel 430 may have acircular, polygonal, or any other cross sectional shape.

FIGS. 9 and 10 illustrate the foot 450 of the illustrative example ofFIGS. 1-13 in greater detail. The hooked portion of the foot 450includes an elbow 462 having a first, proximal portion 464 extendingdistally from the post 452 along a proximal portion axis 465 divergingfrom the bore axis 456 at a first angle 466 relative to the bore axis456. A second, distal portion 468 extends distally from the firstportion 464 along a distal portion axis 469 converging toward the boreaxis 456 at a second angle 470 relative to the bore axis 456. The firstand second angles 466, 470 are chosen to allow the foot to extend into aconfined space, for example behind material such as a portion of softtissue such as a tendon or ligament, and position the receiver 202 so asnot to obstruct the users view of the foot and needle. The first angle466 is in the range of 0 to 180 degrees; preferably 0 to 90 degrees;more preferably 25 to 55 degrees; more preferably 35 to 45 degrees. Inthe illustrative example of FIG. 10, the first angle 466 isapproximately 42 degrees. The second angle 470 is in the range of 0 to90 degrees; preferably 25 to 55 degrees; more preferably 35 to 45degrees. In the illustrative example of FIGS. 9 and 10, the second angle470 is also approximately 42 degrees. An eye 472 is formed through thesecond portion 468, from a proximal facing surface 474 to a distalfacing surface 476, coaxial with the bore axis 456 for receiving thedistal end of the needle 350 when the needle is in the second position.A hole 478 defining a hole axis 480 extends through the second portion468 from the distal surface 476 and intersecting the eye 472. The hole478 permits passing a suture strand from the distal surface 476 of thesecond portion 468 to the eye 472. The hole axis 480 forms an angle 482relative to the bore axis 456. The angle 482 is between parallel to theproximal facing surface 474 of the second portion 468 and parallel tothe distal facing surface of the first portion 464; preferably in therange of 45 to 135 degrees; more preferably 45 to 90 degrees. In theillustrative example of FIGS. 9 and 10, the hole angle 482 isapproximately 90 degrees relative to the bore axis 456. A groove 484 isformed in the proximal surface 474 of the second portion 468communicating from the eye 472 to the distal end 460. A notch 486 isformed through the distal end 460 from the proximal surface 474 to thedistal surface 476 and communicating with the groove 484. The groove 484and notch 486 are sized to receive a suture strand and retain the strandon the distal end of the foot 450. The proximal surface 474 of thesecond portion 468 of the foot 450 provides a supporting platform formaterial through which the needle 350 is passed. The eye 472 allows theneedle 350 to penetrate all the way through the material and intercept asuture strand extending from the hole 478 to the groove 484.

FIGS. 11-13 illustrate the needle 350 of the illustrative example ofFIGS. 1-13 in greater detail. A narrowed shaft 362 extends between theshank 352 and a sharp tip 364 at the distal end of the needle. Ashoulder 366 defines the transition from the shank 352 to the shaft 362.The shaft 362 is generally rectangular in cross section with a top 368,a bottom 370, and opposing sides 372, 374. The corners 376 are rounded.The shaft 362 has a height 378 between the top 368 and bottom 370 and awidth 380 between the sides 372, 374. Both the height 378 and width 380of the shaft are narrower than the shank 352. The width 380 of the shaft362 is greater than its height 378. The ratio of the width 380 to theheight 378 is in the range of 1 to 3; preferably 2 to 3. In theillustrative example of FIGS. 11-13 the ratio is approximately 2.3. Thedistal end of the shaft is tapered in the width dimension from the fullwidth to the tip 364. In the illustrative example of FIGS. 11-13, theshaft is tapered on a single side in the width dimension to form asingle-sided bevel 382. The distal end of the shaft is tapered in theheight dimension from the full height to the tip 364. In theillustrative example of FIGS. 11-13, the shaft is tapered on oppositesides in the height dimension to form a chisel portion 384. A notch 386is formed in the side of the shaft 362 through the shaft 362 from thetop 368 to the bottom 370. The notch 386 has an opening width 388measured parallel to the needle axis 354, a depth 389 measuredperpendicular to the needle axis 354, and a notch axis 392 forming anangle 394 to the needle axis 354. In the illustrative example of FIGS.22-13, the notch has parallel side walls 396, 398 that are parallel tothe axis 392. The notch width 388, depth 389, and angle 394 are selectedto optimize the ability of the needle 350 to capture and retain a suturestrand while avoiding snagging other material through which the needle350 passes. FIGS. 14A-14G illustrate a variety of needle designs havingvarying notch width, depth, and angle. The present inventors havedetermined that the balance between capturing and retaining a suturestrand and avoiding snagging is optimized, in the case of a suturestrand with a diameter D, when the width of the notch is in the range of0.9 D to 2 D. A notch width of 0.9 D creates a press fit depending onthe resilient nature of the suture strand. Preferably, the notch widthis in the range of 1 D to 1.5 D. Similarly, the notch depth is optimizedwhen the depth is in the range of 0.75 D to 3 D. A notch depth of 0.75 Dcaptures the suture but leaves a portion of the suture projecting fromthe notch. Preferably, the depth is in the range of 1 D to 2 D. Thenotch angle is in the range of 30 to 90 degrees; preferably 35 to 55degrees. In the illustrative example of FIGS. 11-13, the notch wasoptimized for a USP#2-0 suture having a diameter in the range of0.300-0.339 mm and has a width of 0.30 mm and a depth of 0.46 mm and anangle of 45 degrees. The notch opens toward the side of the needle 350and suture passer 100. The bevel 382 leads from the tip 364 of theneedle along the narrow side of the needle shaft 362 toward the openingof the notch 386. The needle may be sized to capture and pass one ormore suture strands.

FIGS. 15-21 illustrate loading a suture strand 500, having a first end502 and a second end 504 into the suture passer 100 of FIGS. 1-13. Afirst end 502 of the suture strand 500 is inserted through the hole 478in the foot 450 from the distal surface 476 toward the eye 472 andextended past the proximal surface 474 as shown in FIGS. 15 and 16. Thefirst end 502 of the suture strand is pulled distally to place thesuture strand 500 in the groove 484 as shown in FIGS. 17 and 18. Thesuture strand 500 is wrapped over the distal end 460 in the notch 486and pulled proximally over the distal surface 476 of the second portionof the foot 450 as shown in FIGS. 19 and 20. The ends 502, 504 of thesuture strand are wrapped around the side knobs 228 and 230 and retainedby the O-rings 238, 240. In the example of FIG. 21, the suture strandends are routed proximally to the bottom knob 232 wrapped part-wayaround the proximal side of the knob 232 and secured on the side knobopposite the side on which the end was routed such that the suturestrand is maintained near the center of the suture passer 100 and betterretained on the foot 450.

FIGS. 22-27 illustrate the operation of the suture passer 100. When thebutton 390 is pressed distally, the needle assembly 300 moves distallyrelative to the housing and barrel assembly along the straight-linemotion axis 506 of the suture passer which is coaxial with the needleaxis 354 and foot bore axis 456. As the needle 350 approaches the suturestrand 500, the bevel 382 contacts the suture strand 500 and wedges itsideways increasing the tension in the suture as shown in FIGS. 22 and23. Further advancement of the needle 350 moves the notch 386 towardalignment with the suture strand 500 until the tension in the suturecauses the suture 500 to move into the notch 386 as shown in FIGS. 24and 25. Releasing pressure on button 390 allows the spring 250 to biasthe needle assembly proximally. Depending on the resilience of thesuture 500 and how tightly it is secured to the knobs 228, 230, theneedle may or may not be able to retract. By releasing one or both ends502, 504 of the suture 500, the suture ends can move toward the foot 450and allow the needle to retract and pull a bight 508 of suture 500proximally toward the barrel 430 as shown in FIG. 26. Further retractionof the needle 350 pulls the bight 508 into the barrel 430 (FIG. 27)trapping the bight 508 between the needle 350 and barrel bore 434. Torelease the bight 508, the button 390 is pressed to advance the needle350 out of the barrel 430.

FIGS. 28-46 depict examples of the illustrative suture passer 100 in useto pass sutures through a material to create a variety of stitches.Referring to FIG. 28, the suture passer has been loaded as describedrelative to FIGS. 15-21. The foot 450 is positioned adjacent material510 through which it is desired to pass the suture 500. The secondportion 468 of the foot is positioned behind the material 510 with theproximal surface 474 supporting the material 510. Referring to FIG. 29,the button 390 is pressed to advance the needle 350 through the material510 and capture the suture 500 in the eye 472 of the foot 450. Referringto FIG. 30, the button 390 has been released and the suture ends 502 and504 have been freed from the knobs 228, 230 and allowed to move distallyso that the needle 350 has retracted and pulled a bight 508 of suture500 through the material 510. Referring to FIG. 31, the button 390 hasbeen pressed to release the bight 508 and the first end 502 has beenallowed to drop free from the passer 100. Referring to FIGS. 32 and 33,the second end 504 has been removed from the foot 450 by pulling thepasser 100 proximally away from the bight or by pulling the suture 500distally away from the foot 450. The suture ends 502, 504 have beenpassed through the bight 508 and pulled to form a stitch in the form ofa hitch 512.

Referring to FIG. 34, instead of pulling the ends 502, 504 through thebight 508, the first end 502 has been pulled through the material 510 bypulling on one side of the bight 508 to form a simple stich 514.

Referring to FIG. 35, the passer 100 is prepared for making a runningstitch by pulling suture 500 distally through the foot to create slack516 between the foot 450 and material 510. Referring to FIG. 36, theslack 516 and the second end 504 have been pulled proximally and securedto the knobs 228, 230. Referring to FIG. 37 a second bight 518 has beenpassed through the material 510 in the same manner as the first bight508 and the slack 516 and second end 504 have been released from thepasser 100.

Referring to FIG. 38, the first and second ends 502, 504 have beenpulled through to the front side of the material 510 by pulling on oneside of each of the bights 508, 518 to form a mattress stitch 520 in thematerial 510.

Referring to FIG. 39, instead of the ends 502, 504 being pulled throughthe material the first end 502 has been placed through the first bight508 and the second end 504 has been placed through the second bight 518to form a modified mattress stitch 522 with each end 502, 504 secured bya hitch.

Referring to FIG. 40, a third bight 524 has been pulled through thematerial in the same manner as the first two bights 508, 518. A stitchmay be formed by placing one or both ends 502, 504 through the bights508, 518, 524 to lock the bights as shown in FIG. 41.

Referring to FIG. 42, instead of placing the ends through the bights,the second bight 518 has been looped through the first bight 508, andthe third bight 524 has been looped through the second bight 518 to forma chain stitch 526.

Referring to FIGS. 43 and 44, another alternative to forming stitcheswith three bights is shown. Here, the second bight 518 has been cut toform third and fourth ends 528, 530. The third and fourth ends 528, 530are pulled back through the material 510 and then the first and thirdends 502, 528 are placed through the first bight 508 to form a firsthitch 532 and the second and fourth ends 504, 530 are placed through thethird bight 524 to form a second hitch 534.

Alternatively, as shown in FIGS. 45 and 46, the same construct could beproduced by forming two bights 508, 518, and cutting through the slack536 on the back side of the material 510 to produce third and fourthends 538, 540 which with the first and second ends 502, 504 are used toform hitches 542, 544.

Illustrative examples of instruments and methods have been shown in useto pass suture through material to form illustrative hitches. Thepresent invention is not limited to the specific instruments and methodsdepicted. Furthermore, it is to be understood that instruments andmethods according to the present invention may be used to pass anynumber of bights of suture through one or more materials and form anydesirable construct.

1-12. (canceled)
 13. A system comprising: a suture having a diameter; asuture passer comprising a housing defining a linear motion axisextending proximally to distally; a needle mounted for translation alongthe motion axis between a first proximal position and a second distalposition, the needle having a shaft and a notch formed in the shaft, thenotch having a width measured parallel to the motion axis and a depthmeasured perpendicular to the motion axis, the notch width being in therange of one to one and one-half times the suture diameter and the notchdepth being in the range of one to two times the suture diameter; and afoot mounted to the housing, the foot having a distal portion with aproximal facing surface extending along a distal portion axis crossingthe motion axis, the distal portion having a distal facing surface, thedistal portion axis forming an angle relative to the motion axis, thedistal portion including an opening in the proximal facing surfacealigned with the motion axis and able to receive the needle in thesecond position.
 14. A method of passing a suture through a material,the method comprising: positioning a distal portion of a foot of asuture passer behind the material, the suture passer comprising ahousing defining a linear motion axis extending proximally to distally,a needle mounted for translation along the motion axis between a firstproximal position and a second distal position, a foot mounted to thehousing, the foot having a distal portion with a proximal facing surfaceextending along a distal portion axis crossing the motion axis and adistal facing surface, the distal portion including an opening in theproximal facing surface aligned with the motion axis and able to receivethe needle in the second position; extending the needle through thematerial and into the opening in the distal portion; and retracting theneedle to retrieve a bight of suture from the distal portion proximallythrough the material.
 15. The method of claim 14 wherein extending theneedle comprises constraining the needle to motion along the linearmotion axis throughout its range of motion.
 16. The method of claim 17wherein retracting the needle to retrieve the bight of the suturecomprises retrieving the portion of suture crossing the portion of theopening.
 17. The method of claim 14 further comprising before extendingthe needle: threading a first end of a suture through the distal portionof the foot from distal to proximal and across a portion of the openingsuch that a portion of the suture crosses the portion of the opening.18. The method of claim 16 further comprising, after retracting theneedle to retrieve the bight: releasing the bight from the needle;positioning an intermediate portion of the suture across the portion ofthe; repositioning the distal portion of the foot behind the material;extending the needle through the material and into the opening;retracting the needle to retrieve a second bight of the suture from thedistal portion proximally through the material, the second bight beingconnected to the first bight.
 19. The method of claim 14 wherein thesuture passer further comprises a hollow member extending from thehousing to the foot coaxial with the motion axis and the needle ismounted for translation in the hollow member, and wherein retracting theneedle to retrieve the bight further comprises: retrieving a portion ofthe bight into a distal end of the hollow member to position the portionof the bight between the needle and a wall of the hollow member.
 20. Themethod of claim 14 further comprising: operating an actuator to extendthe needle to the second position; and releasing the actuator to allowthe needle to return to the first position via a spring force.
 21. Themethod of claim 14 wherein the needle further comprises a shaft having afirst side surface and a notch formed in the first side surface, theshaft tapering distally to define a bevel on the first side surfacedistal to the notch, and extending the needle comprises engaging thesuture with the bevel as the needle is extended to deflect the sutureand further advancing the needle until the suture moves into the notch.22. The method of claim 17 wherein the distal portion of the footfurther comprises a hole, and wherein the threading includes passing thefirst end of the suture through the hole.
 23. The method of claim 22wherein the distal portion further comprises a groove formed in theproximal facing surface, a tip, and a notch formed in the tip, whereinthe groove extends from the opening to the notch, and wherein thethreading the first end of the suture across the portion of the openingincludes passing the first end of the suture distal to proximal throughthe hole, across the portion of the opening, into the groove, and beyondthe tip, and passing the first end of the suture distal to proximalacross the distal facing surface such that a portion of the suture ispositioned in the notch.
 24. The method of claim 14 further comprising,prior to positioning the distal portion behind the material, loading asuture onto the suture passer, wherein the suture comprises a first endportion, a second end portion, and an intermediate portion, and whereinloading the suture comprises extending the intermediate portion acrossthe opening and attaching the first and second end portions to thesuture passer.
 25. The method of claim 24 further comprising, afterextending the needle and prior to retracting the needle, detaching atleast one of the first and second end portions from the suture passer.26. A method of operating a suture passer comprising a housing defininga linear motion axis extending proximally to distally, a foot mounted tothe housing, and a needle mounted for translation along the motion axisbetween a proximal first position and a distal second position, whereinthe foot comprises a distal portion extending along a distal portionaxis crossing the motion axis, and wherein the distal portion comprisesa proximal facing surface, and a distal facing surface, the methodcomprising: loading a suture onto the suture passer, wherein the suturecomprises a first suture portion including a first end of the suture, asecond suture portion, and an intermediate suture portion between thefirst suture portion and the second suture portion, and wherein loadingthe suture onto the suture passer comprises: passing the first sutureportion distally through a hole formed in the foot; passing the firstsuture portion distally across an eye formed in the proximal facingsurface and beyond a distal end of the distal portion, wherein the eyeis aligned with the motion axis and is operable to receive the needle inthe second position, wherein the distal end includes a notch, andwherein the proximal facing surface includes a groove extending betweenthe eye and the notch; passing the first suture portion proximally on adistal side of the distal portion; securing the first suture portion tothe suture passer; and securing the second suture portion to the suturepasser; and wherein, with the suture loaded onto the suture passer, theintermediate portion extends through the hole, across the eye, along thegroove and the notch, and around the distal end, and the intermediateportion includes a third suture portion extending across the eye fromthe hole to the groove.
 27. The method of claim 26 further comprisingpassing the suture through a material, wherein passing the suturethrough the material comprises: placing the distal portion of the footof the loaded suture passer behind the material; extending the needlethrough the material and into the eye, thereby forming a piercing in thematerial; engaging the needle with the third suture portion; and withthe needle engaged with the third suture portion, retracting the needle,thereby forming a bight and pulling the bight through the piercing. 28.The method of claim 27 wherein a distal end portion of the needleincludes a bevel, and wherein extending the needle through the materialand into the eye includes engaging the bevel with the third sutureportion, thereby pushing the third suture portion and applying tensionto the suture.
 29. The method of claim 28 wherein the distal end portionof the needle further includes a needle notch formed proximally of thebevel, wherein the applied tension urges the third suture portion intothe needle notch when the needle notch is aligned with the third sutureportion, and wherein engaging the needle with the third suture portionincludes receiving the third suture portion in the needle notch.
 30. Themethod of claim 29 wherein the distal end portion of the needle furtherincludes a first side, a second side, and a needle tip formed on thesecond side, wherein the bevel extends proximally from the needle tipand toward the first side, and wherein the needle notch extends distallyfrom the first side and toward the second side at an oblique angle withrespect to the motion axis.
 31. The method of claim 27 wherein passingthe suture through the material further comprises, after engaging theneedle with the third suture portion and prior to retracting the needle,releasing at least one of the first and second suture portions from thesuture passer.
 32. The method of claim 26 wherein the hole is formed inthe distal portion, extends through the distal facing surface, andintersects the eye, and wherein the hole has a hole axis that forms anangle in a range of 45 to 135 degrees relative to the motion axis. 33.The method of claim 26 wherein the suture passer further comprises afirst knob and a second knob, wherein securing the first suture portionto the suture passer includes wrapping the first suture portion aroundthe first knob, and wherein securing the second suture portion to thesuture passer includes wrapping the second suture portion around thesecond knob.
 34. The method of claim 33 wherein the first knob extendsfrom the housing in a first direction, wherein the second knob extendsfrom the housing in an opposite second direction, wherein the suturepasser further comprises a third knob extending from the housing in athird direction, wherein the third knob includes a first side facing inthe first direction and a second side facing in the second direction,wherein securing the first suture portion to the suture passer furtherincludes passing the first suture portion along the second side of thethird knob prior to wrapping the first suture portion around the firstknob, and wherein securing the second suture portion to the suturepasser further includes passing the second suture portion along thefirst side of the third knob prior to wrapping the second suture portionaround the second knob.
 35. The method of claim 34 wherein the first andsecond directions are transverse to the motion axis, and wherein thethird direction is transverse to the motion axis and the first andsecond directions.